RAPID: Impacts of Hurricane Maria on tropical forest biogeochemistry: short-term response and long-term trajectory

RAPID：飓风玛丽亚对热带森林生物地球化学的影响：短期响应和长期轨迹

• 批准号: 1803044
• 负责人: Whendee Silver
• 金额: $ 15万
• 依托单位: University of California-Berkeley
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2018
• 资助国家: 美国
• 起止时间: 2018-01-01 至 2018-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1803044&HistoricalAwards=false
• 关键词: RAPID; Impacts; Hurricane; Maria; tropical

This research will study the immediate effects of Hurricane Maria on the dynamics of organic carbon and nutrients in a tropical forest and the streams draining that forest to better determine how short-term impacts affect the long-term trajectory of forest and water resources following single and repeated disturbances. Hurricane Maria led to widespread canopy damage and litter deposition on the soil surface and in stream channels within the Luquillo Experimental Forest (LEF) in Puerto Rico. Understanding how organic carbon, phosphorus, and nitrogen within plant detritus are modified during their movement through soils and into streams, including any exchanges with the atmosphere, is critical to determining long-term ecosystem response to disturbance. The research conducted as part of this project will provide insights into the resilience and resistance of the LEF ecosystem, part of the El Yunque National Forest in the US National Forest System. The PI team will work closely with scientists and students in Puerto Rico and facilitate local student and faculty research needs. The investigators will build the project results into a portfolio of presentations and outreach activities centered on the impacts of climate variability on terrestrial ecosystems. The project will promote diversity in science by supporting Puerto Rican students as laboratory personnel, providing training to other Hispanic students and post-doctoral scientists, and promoting gender equity in science through outreach and mentoring activities.This research makes use of a pre-existing hurricane simulation experiment allowing the researchers to test hypotheses about the effects of single and repeated hurricane disturbance on ecosystem processes, including biogeochemical translocations of carbon and nutrients through soil profiles and microbial activities in response to substrate availability and moisture conditions. The research team will quantify the amount of litter deposited on the soil, measure soil carbon and phosphorus fractions, nitrogen mineralization, iron species, aluminum, and pH in soil profiles, soil lysimeters, and stream water. Microbial activity will be assessed while also targeting gene expression related to macromolecular carbohydrate degradation and nitrogen and phosphorus cycling. Transcript data sequenced via Illumina HiSeq will be mapped to assembled scaffolds from pre-existing metagenomes and provide a means of assessing changes in gene expression. The research will provide the first comprehensive experiment of hurricane effects that characterizes the pre- and post-environmental conditions and biogeochemical cycling with soil depth, and across single and repeated disturbances. This group will also be the first to employ novel analyses of microbial activity, transcriptomics, and link this directly with biogeochemical indices in the context of disturbance and recovery.

这项研究将研究飓风玛丽亚对热带森林和排出森林的溪流中有机碳和养分动态的直接影响，以更好地确定短期影响如何影响单次和重复干扰后森林和水资源的长期轨迹。飓风玛丽亚导致波多黎各卢基洛实验森林 (LEF) 内的大范围树冠受损，土壤表面和河道中出现垃圾沉积。了解植物碎屑中的有机碳、磷和氮在通过土壤和进入溪流的过程中如何发生变化，包括与大气的交换，对于确定生态系统对干扰的长期响应至关重要。作为该项目的一部分进行的研究将深入了解 LEF 生态系统的恢复力和抵抗力，LEF 生态系统是美国国家森林系统 El Yunque 国家森林的一部分。 PI 团队将与波多黎各的科学家和学生密切合作，满足当地学生和教师的研究需求。研究人员将把项目成果纳入一系列演示和外展活动中，重点关注气候变化对陆地生态系统的影响。该项目将通过支持波多黎各学生作为实验室人员、为其他西班牙裔学生和博士后科学家提供培训以及通过外展和指导活动促进科学领域的性别平等来促进科学的多样性。这项研究利用了现有的飓风模拟实验，使研究人员能够检验有关单次和重复飓风扰动对生态系统过程影响的假设，包括 通过土壤剖面和微生物活动，响应基质可用性和湿度条件，进行碳和养分的生物地球化学易位。 研究小组将量化沉积在土壤上的垃圾量，测量土壤碳和磷的含量、氮矿化、铁物种、铝以及土壤剖面、土壤蒸渗仪和溪流中的 pH 值。将评估微生物活性，同时还将针对与大分子碳水化合物降解和氮磷循环相关的基因表达。通过 Illumina HiSeq 测序的转录数据将被映射到来自预先存在的宏基因组的组装支架上，并提供一种评估基因表达变化的方法。 该研究将提供第一个关于飓风影响的综合实验，该实验描述了前后环境条件以及随土壤深度的生物地球化学循环以及单一和重复干扰的特征。该小组还将率先采用微生物活性、转录组学的新颖分析，并将其与干扰和恢复背景下的生物地球化学指数直接联系起来。